It was, by Roy Hodgson's own admission, a calculated gamble. On 30 May England will play Peru at Wembley. What if Leighton Baines were injured?

And Hodgson, to give him his due, did not duck the question. That would be the moment that leaving out a player with 107 caps in favour of an 18-year-old, with 45 minutes of international football to his name, could be described as a "very bad selection".

He is not known for his gambles, Roy. But he was not making any attempt to conceal the fact this one could backfire. "I've heard this a lot," the England manager said. "What if Leighton Baines got injured, wouldn't Ashley Cole be theright answer? And, of course, the answer to that is yes. He would be, without a doubt. But Ashley Cole isn't really a cover player.

"Ashley is a No1 man. When I decided Baines might be my No1, I decided the next one would be Luke Shaw. Circumstances could make the decision a very good one or a very bad one. An injury [for Baines] against Peru would make the selection of Shaw a very bad selection."

The same applies, presumably, in either of the following games in Miami against Ecuador and Honduras, though at least, coming after the 2 June cut-off, there is a rule that would allow England to bring in a replacement. Would Cole come out of international retirement? "You would have to ask Ashley that," Hodgson said. "I would like to think so." But he was kidding himself. The idea has been dismissed as "ridiculous" and that is the gamble when Hodgson is willing to admit Cole is a better tournament player than Shaw.

"Time will tell whether the decision was a good one or a bad one because the circumstances move," Hodgson said. "The circumstances [of an injury] … we might have been better off with Ashley. I can't deny that. I'm certain Luke Shaw wouldn't deny that. Then there might be other circumstances whereby I don't have that problem, I don't get the injury [to Baines], we go through the tournament and we get congratulated because we took a decision to give a very young player a big chance.

"We have a very talented player – the subject of a £27m bid [from Manchester United] – who has a fantastic future and who many people might suggest deserves a chance. What I'm saying is we can't cover both eventualities. I can't take them both. If you're going to take a very good young player like Shaw, without experience, you really need to take three left-backs. You need two seniors, because of [the risk of] injury, and then the younger one. You can't do that. Twenty-three did not give me the luxury of three left-backs."

Wait a second. Did Hodgson just say Cole was the best candidate to replace Baines? "I will ask you another question," he countered. "Do you really think when you have a player of Ashley Cole's ability, with 107 caps, you invite him along to a tournament on the basis he might get the odd game because all he is there for is to cover the left-back who has taken his spot? Is that the correct thing to do with a player like him?"

But what if Cole had said yes to that proposition? "I'm sure he would have done. The point with Ashley is a simple one: it was a really difficult decision. His experience – someone who hasn't played so much in the last six months but still can do it – or this fantastic young talent? I made a decision. And we'll see whether it is the right decision, because it will be in hindsight anyway."

And the final word, after it was gently pointed out that what he was saying could arguably make a case for Cole? "I'm losing track here," he said.

For now, it is a hypothetical danger and England cannot be doing too badly if the worst controversy about Hodgson's squad is who goes as reserve left-back. Baines is anything but injury prone – over the past five seasons he has made 40, 53, 45, 47 and 50 appearances – and it would be unfair on Shaw to assume that because he is young he may be overawed.

The bigger issue, perhaps, is that England, as Hodgson acknowledged, may not have the defenders of old. In 2006 the back four were Gary Neville, Rio Ferdinand, John Terry and Cole. The current defence – Glen Johnson, Gary Cahill, Phil Jagielka and Baines – partly explains why the man from Channel 4 asked Hodgson at the squad announcement, held at Vauxhall's headquarters in Luton, whether England were similar to their sponsor in being "dependable, well-made, well-organised, full of energy but ultimately a little bit ordinary".

Hodgson had arrived in a Vauxhall Insignia and, to even louder groans, he was asked whether the squad amounted to a sports car or a family saloon.

But there was a serious point. "In some ways that back four have done pretty well so far," Hodgson said. "If you make comparisons to the past, I'm pretty sure you'll find ways of suggesting the past ones were better but these are the ones that we have."

His squad have an average age of 26 years and 117 days, more than two years younger than 2010 but older than 2006 (25 years 258 days), and that will come down even further if Hodgson's concerns about Phil Jones are borne out. The diagnosis for Jones, with damaged shoulder ligaments, is a three-week lay-off but Hodgson pointed out "there were no guarantees" and that is why John Stones, the 19-year-old Everton defender, has been added to the standby list.

Strikingly there are only six players in the squad who have been to a World Cup. Ten of the players Hodgson has chosen are under the age of 25 but there are still five 30-somethings and another two, Jermain Defoe and Michael Carrick, on the standby list. This is Defoe's third time among England's back-up players but that was the risk when he moved to Toronto knowing Hodgson had no intentions to watch him. As for Carrick, the sad reality is that his name did not crop up once as Hodgson faced an hour of questions. Nobody is making a fuss when his exclusion means a place for Ross Barkley.

"We've had Barkley in this 23 for a while," Hodgson said. "I hope people are realistic with the level of expectation. I don't want people to think every time he gets the ball he can score a goal like he did against [Manchester] City. Or run 40 yards dribbling past people. I don't want people expecting Ross Barkley always to be the Ross Barkley who played against City because I've seen him in other games where he's been different, not played as well and been taken off."

Then Hodgson was asked the question that is mandatory for every England manager at this point. "Yes," he said. "I believe the squad can win the World Cup, otherwise what's the point? But they are empty words." First things first, he has to worry about what happens when Luis Suárez, Edinson Cavani et al put England's defence under pressure in Group D – and that nothing happens in the meantime to make his gamble backfire.